I think that Pangasius (ID) are not really sold here much anymore as they cannot really be kept in anything other than a pond or massive display.
When I ran an LFS (years ago) we were offered them for free all the time as they were too skittish as you say, tended to have damaged faces and outgrew the tanks too quickly.
I kept a pair in the shop in a 7X2.5X2.5 but it was too small and we moved them on to a public display.
That one looks in lovely condition but needs something much larger than a 4X2X2, as does the Gourami.
